Paper is a fantastic material suitable for numerous uses, including
manufacturing notebooks, books, calendars, and magazines, wrapping gifts, and
wrapping items in stores. Paper is widely used in offices for writing, printing
documents, and photocopying. At home, paper is used to clean, to dry things, and
for many other purposes. In short, paper is one of the most versatile and common
products of modern societies. In this article, I will describe how to make
samples of paper and I will outline the theme of recycling raw materials.

Paper is so essential to writing that we couldn't do without it, and yet it
was not invented until several millennia after the invention of writing. So,
what did people write on before the invention of paper? Some dozens of thousands
of years ago, primitive humans started to draw graffiti and paint hunting scenes
on rocks and cave walls. They also carved notches on sticks, shells, bones, and
stones. It seems they used these signs to count things like days, lunar months,
and the animals they bred. From these first paintings and carvings begins the
path that will lead to writing, but also the history of the materials used for
writing begins here. It is of these items that I will speak in this section.

CLAY TABLETS
Writing was invented about 5500 years ago by Sumerians, a people devoted to
agriculture who lived in ancient Mesopotamia. As a medium for their texts,
Sumerians used clay tablets. Clay is basically mud and in their alluvial plains
they had plenty of it. With clay, they prepared tablets in which they etched
pictures or symbols as long as the tablets were still damp and soft enough.
These tablets were then left to dry so that the signs engraved could be kept for
a long time. First Sumerians, then Babylonians and Assyrians used these tablets
primarily for administrative purposes and notating agricultural products
delivered to warehouses near temples. Tablets were often stored on wooden
shelves. The only possible danger would have been water which could ruin the
tablets. Conversely, if a fire were to break out, the clay tablets would undergo
a cooking that would transform them into terracotta, a material impervious to
water and able to last thousands of years. Fires which because of accidents or
war sometimes struck the archives of these ancient people allowed thousands of
cuneiform tablets to be preserved till modern times. Their deciphering by
archaeologists is giving us important information on the ancient civilizations
which produced them.

PAPYRUS
Shortly after the Sumerians, ancient Egyptians developed their own writing. They
took some of their symbols from the Sumerians, but also invented many other
symbols, comprising an original script of their own. Egyptian writing was
prevalently used for sacred and celebratory purposes; for this it came to be
called hieroglyphic (‘sacred writing’). Egyptians sculpted or painted their
writings on stony temple walls and wooden sarcophagi. One of the most important
inventions of the Egyptians was the papyrus, a medium which begins to have some
likeness to paper. Papyrus takes its name from the plant from which it was
obtained. This plant has its roots in water and develops a long cylindrical stem
which ends with a tuft of narrow and long leaves. From the spongy stem of this
plant, Egyptians extracted thin strips that they placed side by side, partly
overlapping them. Subsequently, over the first layer of strips, they
superimposed a second layer, placing the strips transverse to those below. The
natural glues present in this plant’s tissue insured the adhesion of the strips.
Other sheets were often adjoined to the first sheet, rendering strips that could
even be several meters long and that came to be rolled up in volumes. To
improve the possibility of using this surface for writing, Egyptians beat,
scraped, and smoothed papyri during their production. Egyptian scribes wrote on
papyrus using brushes and ink.
http://www.museolibroantico.com/corso_libro_antico.html Pictures of
the fabrication of papyrus.

PARCHMENT
Ancient Egyptians produced a lot of papyrus, part of which was retained for
their own use and the rest to be sold in all of the Mediterranean. Among their
best customers were the ancient Greeks and Romans. Unfortunately, because of
political and economic crises which struck Egyptian society in the last
centuries before Christ, the production of papyrus diminished. The price of the
product increased and it became necessary to find a substitute. In the city of
Pergamus, people started using sheepskin as a medium for writing. From just one
skin, one could get several sheets as it was possible to separate more layers
from the skin. To make them suitable for writing, the skin had to be adequately
prepared. Towards that goal, sheets were scraped to remove fat and flesh, then
put out to dry on frames which kept them tight. The final product was parchment,
a material highly suitable for writing which came to be used in Europe
throughout the Middle Ages, up until the introduction of paper. An old parchment
could be scraped of the previous writing and could therefore be reused. In this
manner, however, many works by Greek and Roman authors have been lost.

PAPER
According to the Chinese, paper was invented in 105 A.D. by an official of the
Emperor, but recent archaeological findings have shown that paper was already
being used in China at least 200 years before this. The Chinese used large
quantities of paper made from rags and vegetable fibers extracted from hemp,
bamboo, mulberry, willow, etc. They also used paper to make fans, hats, clothes,
and other everyday objects. Paper was brought and spread to many Eastern
countries by Buddhist monks.

In 751 A.D., after a thirty-one-year war, Arabs defeated the Chinese in
battle. Among the prisoners taken were paper factory workers who taught the
technique of papermaking to the Arabs. Soon thereafter, Samarkand became an
important center of paper production. As raw materials, the Arabs used linen and
hemp rags. A few centuries later, the art of papermaking came to Egypt, then
Morocco, and from there Spain. The first Spanish paper factory was opened in
1009.

In 1250, Italy became the biggest producer of paper, which came to be
exported to many European countries. To make paper less absorbent, Arabs used
glues derived from vegetables, but this type of paper was susceptible to mold
and quickly deteriorated. By using glues derived from animals, Italians greatly
improved the quality of paper and its duration could reach many centuries. In
fact, today we know of paper documents which are still in very good condition
after more than 700 years from their production. An important Italian
papermaking center was Fabriano, where the watermark was invented. Within about
three centuries, the technique of papermaking spread from Italy to all of Europe
and then to the Americas.

In the beginning, Arabs and Europeans made paper out of rags. As time passed,
the demand for paper quickly increased, so much so that after a while, rags were
no longer sufficient. In search of a substitute to rags, in 1719 a Frenchman,
who had observed wasps while building their nests, suggested
trying wood to make paper. The trials that were carried out were a success and
since then wood has become the main raw material for producing paper.

To separate individual fibers of cellulose from each other, rags and wood
were placed in mortars and beaten by heavy pestles operated by hydraulic wheels.
When the mixture of fibers was ready, workers poured it into vats full of water.
They then immersed special sieves into the vats and extracted them collecting a
part of the suspension of fibers. During the extraction, workers moved the sieve
in order to make the layer of fibers uniform. Then they let the water drain out,
and they placed the layer of fibers on a piece of felt which was placed on a
pile of other sheets and bits of felt. This pile was pressed to squeeze away the
water. Finally, the sheet of paper was hung to dry.

In the beginning of 1800, the French and the English began to build machines
for the perpetual production of paper. Paper machines were equipped with a long
sieve in the form of a moving belt which collected a continuous layer of fibers
from the suspension. During its run, the ribbon of paper under formation has
glue, mineral additives, and other substances added to it; then it is squeezed
of excess water, dried, and rolled. Finally, it is gathered in large rolls and
sent to factories which turn it into newspapers, notebooks, and many other
products. The fabrication of paper by hand is still practiced to produce
precious sheets or for artistic purposes, but this represents a very small
quantity of the paper produced in the world.

Modern paper is therefore produced primarily from wood and it is made up of
numerous cellulose fibers that are held together by glue. Paper can undergo
special treatment in order to make it suitable for whatever intended use. Take
for example the paper used for drawing and watercolors, which must have a
specific thickness, a certain roughness and a certain absorbency, etc. It is
also possible to make paper without adding glue, but the result is a very
absorbent paper. To render it suitable for writing or printing, it is necessary
to lower the absorption of ink which otherwise would spread. For this purpose,
paper is glued, that is, animal or synthetic glues are added to it. To make
paper less porous, more compact and even brighter, it is coated. Coating
consists of adding very fine mineral powders such as kaolin, calcium carbonate,
talc, fossil flour, and an appropriate adhesive such as casein or other types of
glue. The sheet passes through rollers which press it with force (calandering)
and comes out bright.

Often people use tissues or paper napkins to clean the lenses of glasses or
cameras, but the presence of mineral powders make ordinary paper products unfit
for this purpose. In fact, when rubbing on delicate optical surfaces, these
mineral particles cause microscopic streaks which ruin the quality of the lens.
To clean lenses, you can use special paper products specifically produced for
that function, composed solely of pure cellulose.

Unfortunately, certain modern papermaking processes greatly reduce the life
of paper, which within a few years tends to yellow and weaken. Processes exist
which instead produce paper capable of lasting centuries, keeping itself in very
good condition.

The importance of the invention of paper can be better understood if people
think that before its arrival, to make a book in parchment, dozens or hundreds
of skins were needed. Because of its uniformity in thickness, paper made
possible the invention of the printing press. Before the invention of the
printing press, books had to be written by hand. Together, these two innovations
greatly lowered the cost of books and largely contributed to the spread of
culture throughout the world.

Let’s pass to the experiment part of this article. By now, you understand
that to make a sheet of paper, you must first get a suspension of cellulose
fibers in water. Getting these fibers from a trunk is possible, but it would
take too much time and effort. Therefore, we will use newspapers, from which it
is easier to extract fibers. In this manner, we will also experiment with the
possibility of recycling paper.

With wooden boards, make a frame like that of figure 3. Mount the sieve
underneath, with strips of wood and nails enclosing it (figure 4).

Figure 3 - Frame seen from above.

Figure 4 - Frame seen from below.

PROCEDURE:

- soak some of the newspaper in water (it’s better if you let it to set for a
day or two);
- squeeze out the excess water;
- with the mortar and pestle, crush a little bit of paper at a time until you
get a homogeneous paste, consisting of fibers isolated from each other (figure
5);
- repeat this until you have enough paste;
- fill the bowl halfway with water;
- put the paper paste in the bowl and stir it to separate the fibers;
- remove any resulting clumps (a dense suspension of fibers must remain in the
water);
- immerse the frame in the watery suspension in the bowl (the sieve should be
facing the bottom of the bowl);
- slowly remove the frame from the suspension keeping it steadily horizontal;
eventually move the frame to even out the layer of fibers (figure 6);
- wait for the water to drain;

Figure 5 - With mortar and pestle, crush some of the
newspaper
until you get a homogeneous paste in which the fibers are isolated
from each other. Put this paste in a water-filled bowl and stir by
hand to help the fibers separate from one another.

Figure 6 - Immerse the frame in the bowl, collect part
of the fiber suspension, and slowly remove the frame.

- place the smooth side of a sheet of Formica on top of the sheet of paper still
soaked with water;
- press on the Formica a little to drain the water, taking care not to deform
the sieve (figure 7);
- with a sponge, collect water from underneath and squeeze it away every so
often;
- carefully remove the sheet of Formica so that the sheet of paper remains
attached to it (figure 8);
- let the sheet of paper dry. To do this more quickly, you can dry it with a
hairdryer (figure 9).

Figure 7 – Place a sheet of Formica on top of the layer
of fiber extracted and squeeze out the excess water,
without putting too much force on the sieve.

Figure 8 - Gently, remove the sheet of Formica and with it
the sheet of paper, which will again be soaked with water.

- make other sheets of paper, introducing to the suspension some grass crushed
in the mortar;
- (optionally) later introduce some flower petals (without crushing them).

Figure 9 - Drying of the sheet with a hairdryer.

Figure 10 - The sheet of paper produced.

The presence of green and brown vegetable fibers from the grass will give your
sheets a special charm. Also, the addition of petals will contribute to make the
sheets more beautiful. You can even use the paper you will have made to write a
letter.

The paper you make using this procedure (figure 10) will be bright on one
side and opaque on the other. The bright side is more suitable for writing. This
paper is highly permeable by ink, but it is possible to write on it using a
ballpoint pen. If you want to reduce the absorbency of the paper you’ve made,
soak it in a solution of water and gelatin and then let it dry again.

As you have seen, paper is made up of cellulose fibers held together by glue.
By hand or even by means of special machines, it is possible to separate the
fibers of paper from each other and reuse them to make new paper. In the
industrial processes of recycling printed paper, a deinking treatment is often
performed in order to brighten it.

What does recycling paper mean? As you know, to produce paper it is necessary
to cut down trees. Considering the large quantity of paper used in the world (about
300 million tons), every year entire forests are cut down. This constitutes
disruption to nature. Moreover, when paper is no longer needed,
it is often dumped in landfills, but part of it also ends up in the environment,
contributing to pollution. Recycling paper means reducing both the number of
trees cut down and pollution to the environment (figure 11).

Why do we use the term recycling? Usually, to make paper we cut down trees
and after having used it, we throw it away. As figure 11 shows, this corresponds
to a linear movement from forest to landfill. If instead we also use already
used paper to make new paper, rather than going to landfills, paper returns to
the market. Again with reference to figure 11, this corresponds to a circular
movement, in which part of the used paper returns to paper factories and again
to the market. This circular movement can be repeated several times and can be
applied to other materials, garnering the important advantage of notably
reducing the damage to nature caused by our activities.

Other than paper, is it possible to recycle other materials? Absolutely! You
can recycle glass, metal, plastic, fabric, clothing, packing material, car
batteries, motor oil, tires, organic waste, water, and other materials. Though
not intended for recycling but for controlled disposal, pharmaceuticals,
batteries, paint, plaster and other waste which, if left in the environment,
would cause pollution are also collected.

RECYCLING GLASS
Glass is produced by melting sand at high temperatures. In turn, glass items can
be melted again and transformed into new products. Bottles and jars brought to
temperatures between 800 and 1500°C soften and then melt. At this point, the
material is homogenized by stirring, is refined, and is often bleached. It can
then be used to make new glass items. The recycling of glass is very beneficial
in terms of energy conservation.

In addition to recycling, we also need to consider reusing products. Some
types of bottles and other glass containers can be washed and reused dozens of
times. The system of depositing bottles is highly respectful to the environment.
In fact, reusing items is more efficient energy-wise than recycling them.
Knowing how to use products without ruining them means prolonging their life and
reducing the need to buy new ones.

RECYCLING METAL
Metal is produced by bringing certain minerals to high temperatures and adding
melting materials, deoxidizing materials, etc. To be recycled, metal must be
collected and separated by type: steel, cast iron, copper alloys, aluminum
alloys.

Aluminum alloys melt around 550-650°C according to the alloy. Since the
normal production of aluminum from bauxite requires large quantities of
electrical energy, the recovery of this metal is particularly important.

Copper is widely used in making electrical wires. Copper alloys are widely
used in factories. The main copper alloys are bronze (copper + tin) and brass (copper
+ zinc). Copper melts at 1083°C, bronze between 900 e 1000 °C, and brass at
about 900°C. The world reserves of copper are becoming exhausted, making the
recycling of this material important.

In metallurgy, one distinguishes iron (chemical element) from steel, which is
an alloy derived from iron and other elements. Cast iron has a higher carbon
content than steel. When burnt in furnaces for the production of steel, carbon
frees large quantities of carbon dioxide, carbon monoxide, sulfur dioxide, and
pollutes the atmosphere. Steel melts at about 1500°C, is inexpensive, and is not
particularly rare, but the collection and reuse of scrap iron is nonetheless
useful because it reduces the need for extracting iron ore and the amount of
carbon necessary to produce new steel. Because of the presence of nickel in
their alloy, austenitic stainless steel is expensive and recycling it is
important.

RECYCLING PLASTIC
Plastic is derived from oil and is rather costly as well as its producing
processes often being polluting. Many plastics break down very slowly and when
they end up in the environment, they pollute it for a long time. Many dolphins
and whales die because of plastic bags carried to sea by the wind that they end
up swallowing. Recycling plastic is therefore important for economical reasons,
energy conservation, and for reducing pollution to the environment. On the
market, there are many different kinds of plastic such as polyethylene, PVC,
polystyrene, polypropylene, etc. In order to recycle them efficiently, they
could be separated by polymer type. Unfortunately, this is difficult to do, and
for the time being we are limited to a unsorted collection of only a few types
of plastic.

All plastics can be recycled by the process of pyrolysis. Pyrolysis consists
of bringing plastic to a temperature of 500°C in the absence of oxygen. At this
temperature, plastic decomposes producing gases which can be used to make new
plastic or can be burned for the purpose of creating electrical energy.

RECYCLING ORGANIC MATERIAL
Food scraps, cut grass, small pruned branches, fallen leaves, etc. are easily
decomposed by bacteria, earthworms, and other little organisms. At the end of
this process, we are left with a very fertile soil, called compost, for use in
agriculture. To facilitate their transformation into compost, organic waste is
gathered in the appropriate containers (composters) where they undergo the
biological transformation described above. The recovery of organic waste is
important because it is rather voluminous and becomes rather costly for normal
disposal. Moreover, if thrown into dumpsters, the food scraps would dirty any
other recyclable items in the garbage making those items less easily separable
and collectible. Returning organic substances to farmlands or even your own
backyard through composting renders the soil more fertile and reduces the need
for chemical fertilizers.

RECYCLING WATER
Water from the sewage system and from agricultural drains can be purified and
reused. One of the processes of purification consists of making water flow into
lakes or special purifying plants, where the organic substances present in it
are used as food by bacteria and other microorganisms. At the end of the process,
these substances are transformed into mud which sediments at the bottom. Passes
across sand and other procedures complete the purification of water, which can
again be made drinkable. Often, the resulting mud can be used in farming as
fertilizer. Also most of the runoff water from industrial processes can be
purified.

Recycling raw materials is important for reducing the damaging alterations to
the environment produced by human activities. By recycling raw materials, we
collect a smaller amount of raw material from nature and also reduce the amount
of waste. Important steps in recycling raw materials include sorting them at
home and in the office and a sorted garbage collection. Through sorted garbage
collection, those materials which before were just throwaways that went towards
polluting the environment have become more and more of an economic resource.
Nowadays, an industry for the recycling of raw materials is on the rise.
Companies which specialize in the online advertisement and sale of industrial
waste which can be useful to other companies have also been born.

The analysis of the life cycle of products, or Life Cycle Assessment
or Life Cycle Analysis (LCA), is an evaluation of the influence of
products on the environment (environmental impact), calculated from their
creation to their disposal. Studying the life cycle of a product means analyzing
the materials used to produce it, the method of extracting the raw materials,
the production process employed, how it is marketed, how and for how long it is
used, and how it is disposed of. Life cycle analysis is calculated with
reference to the environment, considering how the environment is altered at each
stage of the product’s life. From this analysis, we can arrive at valuable
directions on reducing the collection of raw materials from the environment and
subsequently better recycling them. This analysis can also suggest which
materials to use and which processes of extraction, manufacture, use, and
disposal are most sustainable with respect to the environment (eco design). The
object of LCA can also be activities and services, for example sanitation
services, postal services, and obviously many other activities which do not
yield tangible products but offer equally important social benefits.

In the course of this article, you have seen how paper is made and how it is
possible to produce beautiful sheets of paper at home with little expense and
limited equipment. Making paper with your own hands is without a doubt an
interesting activity. It is also fascinating to know that the paper we use so
nonchalantly is the fruit of a long journey, begun thousands of years ago when
our ancestors took to drawing graffiti and paintings on rocks. From rocks, we
passed to clay tablets, then papyrus, parchment, and only at the end, to paper.
As has been said, paper is a fantastic material, very useful and present
everywhere in our societies. The recent arrival of computers seems to put into
question the existence of paper, which, according to some, is destined to
disappear.

By now, several years have passed since we entered the computer age. More and
more we read documents on monitors rather than paper. We record documents on
media such as disks, but the use of paper has not abandoned and perhaps it hasn’t
even diminished. Paper continues to be a part of our lives and many of us still
prefer to read books on paper instead of on a screen. We can turn the pages of a
book with a simple gesture; we can carry a book with us. Reading a book on a
monitor is not as comfortable and our eyes tire quickly. Moreover, reading a
book on a screen forces our bodies into an unnatural stationary position which
after a while tires us.

Electronic devices dedicated to the reading of books, newspapers, and other
documents on a flat screen are appearing. These devices allow you to read a page
at the time and to move to the next page by pressing a key. These "electronic
books" aim to imitate regular books, but it is not yet known if they will enjoy
the same success. On the horizon, we foresee books, magazines, and newspapers
made of electroluminescent plastic sheets which will receive the news from the
Internet.

The computer medium on which people write or draw is intangible, or rather,
it is made up of different kinds of disks; but on these disks we cannot see
anything, and to read them, it is necessary to insert them into a suitable
reader. The material on which are documents are saved is perishable. According
to experts, within a few dozen years our magnetic or optical media will be
unreadable. It’s a real shame for a technology as complex as ours to not even
withstand comparison in terms of durability to cuneiform tablets which have
retained their information for over 5000 years!

In this article, you have seen how recycling paper is possible and useful,
and from there we moved on to discussing the recycling of other materials. You
may have also realized how useful and important recycling is in reducing the
collection of raw materials from nature and in minimizing environmental
pollution. While scientists study new methods of recycling and many companies
analyze the life of products in order to reduce their environmental impact,
companies which turn waste into resource are booming. The world is constantly
changing and I am convinced that paper will survive the computer era wonderfully,
and most likely, paper will stay with us for a long time to come.